I. Field of the Invention
This invention relates to a coil spring for a faucet assembly and, in particular, to a faucet spring which in addition to urging the seal member into contact with the movable valving member prevents damaging debris from contacting the valving member.
II. Description of the Prior Art
One of the features of a washerless faucet is the resilient seal element which cooperates with the valving member to ensure complete shut-off of fluid flow when the valve is moved to the off position. Generally, the seal element is seated within a smaller secondary bore offset from the center of the main bore which houses the valving member. In order to maintain sealing contact between the seal element and the valving member, means are normally provided to urge the seal against the bottom of the valving member. Such means may be provided by the resilient properties of the seal when the seal element is axially compressed within the secondary bore. Alternatively, a spring may be utilized to urge the seal upwardly to ensure engagement.
Because the seal element and/or the spring form a tubular flow passage leading to the valving member, debris found in the supply lines of the faucet will be forced through the passage under the force of the water pressure into contact with the valving member. Certain types of debris can damage the valving member or jam its operation as it is rotated.
Such damaging debris can even be in the lines unnoticed before the new washerless faucet is installed. Oftentimes the retaining screws for a valve washer in an old faucet can loosen and drop into the supply line. After the old faucet is replaced by the new washerless faucet and the water is turned on, the screw can be forced up against the valving member by the pressure of the fluid flow resulting in damage to the valve. When the water pressure is turned off to investigate the malfunction or to replace the valve, the screw can fall back into the supply line unnoticed. This routine can occur repeatedly until the frustrated consumer gives up on the new faucet assembly. Many times the only evidence of the recurring problem is the set of thread marks left on the valve member by the screw. To date no means have been developed to prevent such large debris from engaging the valve seat while maintaining the efficient operation and low cost of the washerless faucet valve cartridge.